Press anvils



Sept. 20, 1966 J. H. BEARD 3,273,490

PRESS ANVILS Filed Sept. 24, 1964 5 Sheets-Sheet l VN @N @www Q@ E ATi-maw EVS INvENw-oz JACK H. E ARD Bv lmww um @wikis J. H. BEARD PRESS ANVILS Sept. 20, 1966 13 Sheets-Sheet 2 Filed Sept. 24, 1964 x l 1 l I 1 INvENTcR J. H. BEARD BY ,wvgewum Mug AT1-aannam United States Patent O 3,273,490 PRESS ANVILS Jack Herbert Beard, Sheleld, England, assignor to Davy and United Engineering Company Limited, Shetlield, England Filed Sept. 24, 1964, Ser. No. 399,018 Claims priority, application Great Britain, Sept. 26, 1963, 37,857/ 63 11 Claims. (Cl. 100-229) This invention relates to press anvils.

In order to provide a sliding anvil with a stroke which is substantially greater than that of a hydraulic cylinder which can be manufactured economically, it is usual to attach the anvil to a drag bar by means of a drop pin and to attach the drag bar, in turn, to the cross heads of two opposed rams eaoh having a stroke such that the stroke of the anvil is a multiple of it. To move the anvil through its full stroke, it is then necessary to move the anvil through one ram stroke, withdraw the drop pin by external means (eg, a shop crane or independent hydraulic means), and return the rams to their original positions and replace the drop pin in the anvil to engage `a second hole in the drag bar. A second stroke of the rams is then able to move the anvil a further distance equal to the stroke of the ram. This method has the disadvantage that the drag bar and its slides are expensive to manufacture and repositioning of the drop pin is both dii'licult and time-absorbing.

According to the present invention a press anvil is provided with a pair of double acting hydraulic piston and cylinder assemblies arranged on opposite sides of the press center, one assembly being couplable to the anvil to move the anvil toward and away from the press center position, and the other assembly being couplable to the anvil to move the anvil toward and away from the press center position on the other side of that posit-ion. The anvil is alternatively coupled to one or other of .the assemblies according to its position.

Preferably the coupling means are arranged such that when the anvil, coupled to a rst of the assemblies and disengaged from the second of the assemblies, is moved beyond a predetermined point toward the second assembly, the anvil is automatically decoupled 'from the irst assembly and coupled to the second assembly.

In a preferred form the anvil is formed with a pair of recesses, and each assembly is provided with a pin attached to its movable member, normally a iirst of the pins associated with a irst of the assemblies being engaged with its associated hole, while the other pin is held disengaged from the anvil, and including means for automatically releasing said other pin to engage its recess and automatically withdrawing t'he first pin from its recess, when the tirst assembly approaches the limit of its stroke in the direction towards the second assembly.

In a further aspect the invention provides apparatus for moving a horizontally slidable press anvil, comprising a iirst double act-ing piston and cylinder assembly located on one side of the press center line, first coupling means for coupling the rst assembly to the anvil for moving the anvil on that side of the press center line, a second double acting piston and cylinder assembly located on the opposite side of the press center line, second coupling means for coupling the second assembly to the anvil for moving the anvil on that side of t-he press center line, and means for automatically disengaging the anvil from either assembly when it approaches the limit of the stroke of that assembly in a direction towards the other assembly, and automatically coupling that other assembly to the anvil.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings of which:

FIGURE 1 is a diagrammatic view of an anvil and means for moving the anvil, the anvil being shown in its central position;

FIGURE 2 is a view showing the anvil of FIGURE 1 in its furthest left position;

FIGURE 3 is a partial plan view on an enlarged scale showing in greater detail the portion of the application illustrated at the extreme right of FIGURE l;

FIGURE 4 is a partial vertical section showing the portion of the apparatus illustrated in FIGURE 3 and taken in a plane passing through the longitudinal axis of the piston rods 15a, 16a; `and FIGURE 5 is a partial vertical line V-V of FIGURE 4.

An anvil 12 is slidable on support 13 to the left or right of the drawing about a press center line 14. A pair of lcylinders 15, 15a located on opposite sides of the press center line, have piston rods 16, 16a attached to crossheads 17, 17a. Carried in recesses 19, 19a in the crossheads respectively are vertical slidable pins 18, 18a having heads 20, 20a and carrying rollers 21, 21a at their bases. The pins are biased upwardly by springs 22, 22a compressed between heads of the pins and `the bases 23, 23a yof the recesses 19, 19a.

Slidable iloor plates 26, 26a are coupled to opposite sides of the anvil by cooperating pairs of hook-like abutsection taken along the I.ments 24, 25 and 24a and 25a. The iioor plates 26, 26a

`are formed with recesses 27, 27a respectively in their bases arranged to receive the iheads 20, 20a of the pins 18, 18a. An abutment 28 on the iloor plate 26 is arranged to engage an abutment 30 on the cross-head `17 to drive the anvil to the right when cross-head 17 is driven to the right by piston rod 16. Similarly, vabutments 28a fon floor plate 26a and 30a on crosshead 17a are arranged to engage one another when the anvil is driven to the left by piston rod 16a. Thus the cross-heads and slide plates are not driven through the pins 20, 20a except on the outward extending strokes of the piston rods 16, 16a. When abutments 28, 28a engage abutments 30, 30a, respectively, the pins 20, 20a are coaxial with recesses 27, 27a, respectively. Channels 31, 31a are provided in the base of the floor plates 26, 26a, respectively, to clear the abutments 30, 30a on the cross-heads- Wedges 32, 32a are mounted `on the support 13 so as to engage the rollers 21, 21a, respectively, in the withdrawn position of the piston rods `16, 16a. As each piston rod approaches its fully withdrawn position its associated roller rides up its associated wedge to withdraw the head 'of the pin from its recess in the floor plate. Each roller will rest on the thickest part of the wedge with the head of the pin entirely withdrawn from its recess when the piston rod is fully withdrawn, having reached the limit of its stroke towards the press center line and the other piston and cylinder assembly.

The recesses 27, 27a are covered by cover plates 33, 33a respectively to prevent ingress of scale. The crossheads 17, 17a, respectively carry strikers 34, 34a which are arranged to actuate limit switches 35, 35a, respectively.

The stroke of each of the piston and cylinder assemblies slightly exceeds half the stroke of the sliding anvil, the excess stroke being used to disengage the connecting pin between one assembly and the anvil whilst engaging the connecting pin between the other assembly and the anvil. In the center position of the anvil, shown in FIGURE 1, neither piston rod is entirely Withdrawn. FIGURE 2 shows the position of the anvil after a full stroke to the left. In this position the piston rod 16 is fully extended while piston rod 16a is fully withdrawn, the pin 20* is engaged in the recess 27 while pin 20a is withdrawn against the action of springs 22a by wedge 32a, `and limit switch 35a is depressed by striker 34a.

In operation, to move the anvil from its fully left position shown in FIGURE 2, to its fully right position, first the annulus side of cylinder is supplied with pressurized oil which drives the piston rod 16 to the right. This drives the anvil 12 to the right through cross head 17, abutment 30, abutment 2S, and floor plate 26. Shortly before roller 21 begins to engage the thin end of Wedge 32, and shortly before the anvil reaches the press center position, the abutment 23a engages the `abutment 30a, and the recess 27a is aligned with the pin 18a. As the anvil moves to the press center position roller 21 begins to ride up the wedge 32 withdrawing pin 13 from the recess 27, against the action of spring 22, while roller 21a moves down the wedge 32a releasing the pin into the recess 27a. This motion of pin 18a is caused by the abutment of 28a and 30a which causes the floor plate 26a to drive the cross head 17a to the right beginning to extend piston 16a. During movement of the rollers 21, 21a over the wedges 32, 32a the pins and their recesses remain coaxial, so that there is no resistance to movement of the pins. As soon as crosshead 17a begins to move to the right the striker 34a releases the limit switch 35a. I ust after roller 21 has reached the thickest part of wedge 32 so that pin 18 is entirely withdrawn and pin 18a entirely located in the recess 27a, striker 34 will depress limit switch 35, which is arranged to operate the hydraulic circuit to redirect pressurised oil from the annular side of cylinder 15 to the head end of cylinder 15a. The anvil 12 will then be moved to its fully right position by the pin 13a pulling the anvil, until the piston rod 16a is fully extended.

FIGURE l also shows a hydraulic circuit diagram, suitable for operating the piston and cylinder assemblies 15, 15a. A pump 36 powered by motor 37, and having a relief valve 38 provides a pressurised supply to valve 49 on line 41. Valve 40 is normally biased to a closed position in which the line 41 is connected to a drain, but can be energised by solenoid 42 to connect the supply to a line 43. Line 43 is connected to valves 44, 45, which are sh-own in their oit positions in which the output terminals are both connected to a drain. Energization of solenoid 46 of valve 44 connects line 43 to the head end `of cylinder 15 through line 47. Energization of solenoid 48 of valve 44 connects line 43 with the `annulus end of cylinder 15 through lines 50, 51 `and non-return valve 53. The annulus side of cylinder 15 is also connected to line 43 through the non-return valve 53, and to a valve 54. Valve 54 is biased to connect the line 50 to a drain, but can be energized by solenoid 55 to disconnect line 50 from the drain. Energization of solenoid 4S also connects line 47 to a drain.

Energization of solenoid 55A of valve 45 connects line 43 to the .annulus end `of cylinder 15a through a nonreturn valve 60, while connecting the head end of cylinder 15a to a drain through line 57. Energization of solenoid 58 of valve 45 connects the line 43 to line 57. The annulus end of piston 15a is further connected to line 43, and to valve 61. The valve 61 is normally biased to connect the annulus end of cylinder 15a to a drain, but can be operated by energization of solenoid 62 to disconnect this end of cylinder from the drain.

Thus, to move the anvil towards the press center line from a position well to the left of center, operation of an electrical control will energize solenoids 55, 4S and 42. Hydraulic uid will then ow to the annulus of cylinder 15, tiuid from the head end being exhausted to drain. When the piston 16a is pulled out of its cylinder 15a as previously described, fluid will be drawn into the head end through the valve 45, `and fluid will be exhausted from the annulus through the valve 61. When the limit switch 35 is depressed solenoids 55 and 48 will be deenergized and solenoids 62 and 5S will be energized. Thus, piston rod 16 will stop and piston rod 16a will continue the movement in the same direction. Movement from a position well to the right of center will similarly ibe accomplished by energizing solenoids 42, A and 62, and later by means of limit switch 35a de-energizing solenoids 62 and 55A and energizing solen-oids 46 and 55.

In order that the velocity of the anvil shall remain substantially constant, the areas of annulus and piston rod of each piston are made substantially the same and the iiow from the annulus is passed to the inlet side of the directional control valve 44 lor 45 to join the pump output -to the head side. Thus in one direction the pump is eiiectively operating on the piston rod area and in the other direction it is operating on the area of the annulus. As stated, if those areas are .substantially equal then the velocities of movement in either direction will be substantially the same.

It will be appreciated that should movement to the right be required when limit switch 35 is already depressed when solenoids 42, 62, 58 will automatically be energized immediately instead of solenoids 4Z, 55 and 48 to effect the movement. Similarly if limit switch 35a is already depressed and a movement from right to left is required, then solenoids 42, 55 and 46 will automatically be energized instead of solenoids 42, 62 and 55A in order to effect the movement.

I claim:

1. Apparatus tor moving a press anvil relative to a press center position midway of the path of travel of said anvil, said apparatus comprising a pair `of double acting hydraulic piston and cylinder assemblies arranged on opposite sides of said press center position, means for coupling one assembly to the anvil to move the anvil towards and away from the press center position `on -one side of the press center position, and means for coupling the other assembly to the `anvil to move the anvil toward and away from the press center position on the other side of that position.

2. Apparatus for moving a horizontally slidable press anvil relative -to a press center line bisecting the path of travel of said anvil, said apparatus comprising a iirst double acting piston and cylinder :assembly located on one side of the press center line, rst coupling means for coupling the rst assembly t-o the anvil for moving the anvil on that side of the press center line, a second double acting piston and cylinder assembly located on the opposite side of the press center line, second coupling means for coupling the second assembly to the :anvil for moving the anvil 4on that side of the press center line, and means for automatically disengaging the anvil from either assembly when it approaches the limit of the stroke of that assembly in a direction towards the other assembly, Iand automatically coupling that other assembly to the anvil.

3. Apparatus according to claim 2 comprising limit means defining the strokes of the iirst and second assemblies driving the anvil, said limit means being so positioned that said strokes overlap at the press center line.

4. Apparatus according to claim 3 in which each coupling means includes a part provided with a trecess and movable with said anvil .and a coupling member carried by its associated assembly, said coupling member being movable vertically to engage in or disengage from said recess.

5. Apparatus according to claim 4 in which each coupling means includes means arranged to urge the coupling member into engagement in its associated recess.

6. Apparatus according to claim 4 in which each assembly carries an -abutment arranged to engage an associated abutment carried by the anvil when its coupling member is aligned with the associated recess.

7. Apparatus according to claim 6 in which each assembly is arranged to drive the anvil through engagement of its associated abutments for movement towards the other assembly, and is `arranged to drive the other assembly through engagement of the other pair of abutments during the overlapping portions of the strokes of the assemblies.

8. Apparatus according to claim 4 in which the means for automatically disengaging the coupling means from the anvil, comprises fa withdrawal member carried by each coupling member and a xed wedge arranged to engage with its associated withdrawal member when that withdraw-al member approaches the limit of its stroke towards the other assembly, such that the withdrawal member rides up the wedge to Withdraw the coupling member from its associated recess.

9. Apparatus :according to claim 2 in which each assembly carries la striker and including xed limit switches #associated with the assemblies .and arranged to be actuated by the associated strikers when each striker is at the end of its stroke towards the other assembly, together with means actuated by said limit switches for individually connecting and disconnecting said cylinders to .a source of fluid pressure.

10. Apparatus according to claim 9 in which the limit switches are arranged to operate hydraulic valves to redirect pressure uid from xone assembly to the other assembly.

References Cited by the Examiner UNITED STATES PATENTS 2,176,543 10/1939 Norton 83-563 2,940,384 6/1960 Munschauer et al. 10U-214 2,996,025 8/ 1961 Georgei 72-446 FOREIGN PATENTS 678,935 7/1939 Germany. 960,209 6/ 1964 Great Bri-tain.

WALTER A. SCHEEL, Primary Examiner.

11. Apparatus according to claim 10 in which each 20 BILLY J. WILHITE, Examiner. 

2. APPARATUS FOR MOVING A HORIZONTALLY SLIDABLE PRESS ANVIL RELATIVE TO A PRESS CENTER LINE BISECTING THE PATH OF TRAVEL OF SAID ANVIL, SAID APPARATUS COMPRISING A FIRST DOUBLE ACTING PISTON AND CYLINDER ASSEMBLY LOCATED ON ONE SIDE OF THE PRESS CENTER LINE, FIRST COUPLING MEANS FOR COUPLING THE FIRST ASSEMBLY TO THE ANVIL FOR MOVING THE ANVIL ON THAT SIDE OF THE PRESS CENTER LINE, A SECOND DOUBLE ACTING PISTON AND CYLINDER ASSEMBLY LOCATED ON THE OPPO- 